Electronics & Music Maker - Oct 1983 Rumblings

Rumblings

Electronics & Music Maker - Oct 1983 Rumblings

Rumblings

Magazine Archive

Article Group:Computer Musician

Rumblings

The latest buzz from the computer world

ZX81 with EDP synths and E&MM drum generator.

Rumour has it that there's a pile of dead ZX81s beneath a certain window in NW5. Apparently, Sinclair ULAs have a habit of going to the Great Uncommitted Logic Array In The Sky when downloaded via the cassette port from an Apple. The message is don't try pretending you're a cheapo cassette machine! Such noble euthanasia of the Sir Clive kind has been for the cause of us computer musicians in the shape of AMICS and a couple of Fireflies. Er. what? AMICS stand for 'A Music Interpretative Compiler and Sequencer' — composing software, in other words. The Firefly, on the other hand, is a couple of de-keyboarded Gnats in a tasteful wooden case. AMICS is likely to reside in ROM in place of the ZX81's Operating System (or whatever it calls itself), thereby turning the elegant door stop into a dedicated music processor. Between the ZX81 and Fireflies there's an interface box (ZXIF) that includes its own cassette interface with data verify. Preliminary specs suggest that the package will provide for 4,000 notes sequencing with 4 voices and that it'll come with a drum sync and keyboard interface. Provisional prices are £250 for the two voice version and £450 for four voices. That doesn't include the ZX81! We'll have a full report on this as soon as there are signs that ZX81s have ceased trying to turn themselves into garden gnomes... Meanwhile, you may like to dig out E&MM issues for Dec. '81, Feb. '82 to find circuits for a 7-voice EDP synth system and stereo drum generator for the ZX81.

The Grand Poobar of Casio Mods, Robin Whittle, sent me his fascinating bulletin on getting-more-out-of-these-keyboards-than-you'd-ever-imagine-possible. If you've got an M-10 or MT-30 lurking behind your bookshelf/bed/keyboard stack, then dig it out and add all the goodies that Robin talks about in this press release: "An 18 page booklet, 'Modifying the Casiotone instruments', gives details of extra features which may be added to the Casiotone M-10, MT-30, MT-31, MT-40, CT-101, CT 202. These instruments can have their musical range greatly increased by new controls such as filter bypass, octave drops, half speed octave drop, hold, and hard/soft or fast/slow vibrato. An external circuit facilitates computer interfacing and coupling two instruments as master and slave. This technical bulletin is available for £4 (cash or bank cheque) from Robin Whittle, (Contact Details)."

Robin talks about the MT-65 in glowing terms — particularly abut the special sound LSI in this unit which actually puts out 16 bits of data to the DAC. In fact, the model you or I can buy in shops only uses 14 of the 16 bits, so Casio are actually under selling themselves. One of the nice things about this LSI (called the uPd 931) is that the sum of all the notes is put out with a sampling rate of 600 kHz (phew!). By my reckoning that translates into a 75 kHz sample rate per channel, so it's basically bye-bye to all that aliasing hassle! More than that, the data going to the 931 from the main processor includes waveform and envelope specs, which should mean that home micro interfacing is a definite possibility. As Robin says, "the 931 is clearly like Aladdin's Cave — a small entrance leads to many corridors and treasure chests, some of which have never been fully explored." He's now working on loading voices directly from his CP/M system into some 931s he's acquired. We 'll keep you posted on future Whittlings at the Casio stick...

Continuing the Casio connection, Serge Modular Music Systems have recently announced their 'N Voice Controller', a "microprocessor-based digital-to-analogue converter that converts most inexpensive Casio keyboards to a monophonic/polyphonic keyboard with voltages, gates and triggers for controlling analogue synthesisers." Serge suggest that the interface will work with models MT-10, MT-30, MT-31, MT-40, CT-201, and CT-202. The idea behind this is that the Cash's own internal waveforms can be further processed using a few voltage-controlled modules in an analogue synth. Serge claim that "the combination of a Serge voice with a processed Casio sound is an extremely versatile voice, 'fatter' than the fattest synthesiser sounds from a monophonic instrument." The only dampener on what sounds a really good idea is the price — $650. Serge can be reached at (Contact Details).

Well on the way are a couple of really smooth British (about time too...) programmable digital sound generator add-ons for home micros. Specs are elusive at present, but one would appear to have 12 channels each with a 64 kHz sampling rate and offering all sorts of yummy modulation options, whilst the other goes for more channels (32) with a lower sampling rate of 32 kHz. The former is expected to appear initially for the BBC Micro and, not surprisingly, Acorn are showing a lot of interest. With expected price tags of under £200, these look just like what the doctor ordered...

Jen Computer Music System

Jen (the Italian synth manufacturer) exhibited their version of the alpha-Syntauri/Soundchaser keyboard-type add-on at the British Music Fair at the beginning of August. Offering 4-track soft recording facilities and three-oscillator digital voices, it sounded fairly impressive. The price tag of around £1,200 seems a bit steep, though, bearing in mind what the competition is up to these days. The system runs on either the inevitable Apple II or IIe or their own Apple lookalike. The trouble with Apple lookalikes is that you have to contend with Apple's wizzo team of injunction-seeking solicitors. Apple don't like people copying their ROMs, so they do their darndest to boot you into hyperspace. It must be really hard work being a Pineapple or an AMI II or an Apollo II or a Franklin Ace or a Basis 108 or a...